Perl 5 version 20.0
documentation

values

In list context, returns a list consisting of all the values of the named
hash. In Perl 5.12 or later only, will also return a list of the values of
an array; prior to that release, attempting to use an array argument will
produce a syntax error. In scalar context, returns the number of values.

Hash entries are returned in an apparently random order. The actual random
order is specific to a given hash; the exact same series of operations
on two hashes may result in a different order for each hash. Any insertion
into the hash may change the order, as will any deletion, with the exception
that the most recent key returned by each or keys may be deleted
without changing the order. So long as a given hash is unmodified you may
rely on keys, values and each to repeatedly return the same order
as each other. See Algorithmic Complexity Attacks in perlsec for
details on why hash order is randomized. Aside from the guarantees
provided here the exact details of Perl's hash algorithm and the hash
traversal order are subject to change in any release of Perl.

As a side effect, calling values() resets the HASH or ARRAY's internal
iterator, see each. (In particular, calling values() in void context
resets the iterator with no other overhead. Apart from resetting the
iterator, values@array
in list context is the same as plain @array
.
(We recommend that you use void context keys@array
for this, but
reasoned that taking values@array
out would require more
documentation than leaving it in.)

Note that the values are not copied, which means modifying them will
modify the contents of the hash:

Starting with Perl 5.14, values can take a scalar EXPR, which must hold
a reference to an unblessed hash or array. The argument will be
dereferenced automatically. This aspect of values is considered highly
experimental. The exact behaviour may change in a future version of Perl.

To avoid confusing would-be users of your code who are running earlier
versions of Perl with mysterious syntax errors, put this sort of thing at
the top of your file to signal that your code will work only on Perls of
a recent vintage: